Question

Who discovered Auxin?

Answer 1

Auxin is a plant growth regulator. These are the chemicals which alter the physiological processes taking place inside a plant and affecting various metabolic processes in the plants. It is positive for plant growth as it increases the growth. It is sensitive to sunlight and responds to it accordingly.

Complete answer:
It was discovered by- Charles Darwin and Francis did some experiments on coleoptiles. It was to expose the coleoptiles to light (unidirectional source), and found out that they bend towards the light. By covering up some parts of the coleoptiles, they observed that light can be detected by the tip. The seedlings showed no such signs of growing towards light if the tip was covered. They both came to the conclusion that the tip was responsible for light sense, and a messenger is transferred downwards and causing it to bend.
Frits Warmolt Went stated that the chemical messenger is transmitted from coleoptile tips. His experiment showed how the chemical causes a coleoptile to grow towards the light. When these chemicals were distributed equally the coleoptile grew straight, if unevenly, the coleoptile turned towards the light. He then named the chemical auxin that becomes unequally distributed in the bending region. Went also stated it acts by promoting cell elongation.

Note:
Auxin is an essential plant growth regulator for cell growth which affects cell division and cell expansion. Concentration level of auxin, with other factors, causes cell differentiation and specification. It depends on the specific tissue that it may promote axial, lateral or iso-diametric expansion. Auxin promotes cell division and expansion. Auxins and other growth regulators interact to determine patterns of plant development.